Flexible wiring circuit boards are used in electronic appliances in which a wiring circuit is required to have flexibility, such as hard-disk drives. For the purpose of improving workability and suitability for connection, a reinforcing plate is superposed on flexible wiring circuit boards.
However, in some cases, when a plate-reinforced flexible wiring circuit board is repeatedly flexed, a tear originated from the intersection point of the edge of the flexible wiring circuit board and the edge of the reinforcing plate may be developed.
Patent document 1 describes a flexible printed circuit board in which the angle formed by the end line of the reinforcing plate and the visible outline of the flexible printed circuit board is set to be 15 degrees or larger and 30 degrees or smaller.
Furthermore, patent document 2 describes a plate-reinforced flexible circuit board in which a central part of the edge of the reinforcing plate has a partly-protruding shape such as a circular-arc shape or a trapezoidal shape.
Patent Document 1: JP-A-10-135581
Patent Document 2: JP-UM-B-05-034127